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Exercises

  1. Read and translate the text.

  2. Make a detailed plan of the text.

  3. State the main idea of the text and make the annotation.

Text 11 partitions

Partitions are walls which are used to divide building into rooms, corridors and cubicles. They also often act as deep trusses to support the joists of floors, purling and ceiling joists of roofs, etc. Partitions may be classified under following: timber, clay and terra-cotta, concrete, sawdust concrete, plaster, wood-wool cement, asbestos-cement, and metal.

Timber Partitions. – they consist of vertical members called studs, which are secured to two horizontal lengths of timber, the upper being the head and the lower, the sill. One or booth may be either lathed and plastered or covered with boarding, plywood sheets, wall boards, etc.

This class of partition is in common use. Because of its lightness, it is usefully employed when there is no supporting wall below. A disadvantage is its deficient fire-resisting quality.

Clay and Terra-Cotta Brick and Block Partitions – the commonest type of clay partition is the ordinary solid brick.

Wall of 4 ½ in. or more in thickness. Such walls are relatively strong and fire-resisting, but their weight precludes their use for partitions on upper floors unless provision in the form of girders or lower wall is made for their support. Holly clay units, either bricks or blocks, are comparatively light and yet are sufficiently strong for the construction of non-load bearing partition. In general, the blocks are built in cement mortar and are bonded in the usual way with staggered vertical joints. The following are the merits of this blocks: satisfactory mechanical strength, lightness in weight, good head and sound insulation, fireproof, non-shrinkage and vermin proof.

Precast Concrete Block Partition – both solid and hollow blocks are made. There are three of precast concrete blocks, namely:

  1. Concrete blocks used for load bearing walls and made of dense aggregate such as broken stone, heavy blast furnace slag and crushed bricks.

  2. Concrete blocks used for load bearing wall and made of lighter aggregates including foamed slag, clinker, expanded state and pumice.

  3. Concrete blocks used for load bearing partitions and made of aggregates similar to those for type 2.

Sawdust Concrete Blocks Partitions – Sawdust concrete (so called because it is a mixture of cement and sawdust) is used in the production of building and partition blocks. They are composed of cement, fine aggregate and chemically treated sawdust. They are light in weight and have satisfactory heat insulation and fire-resisting values.

Plaster Slab Partitions – these are made of calcium sulphate. This is mixed with water, and sand may be added to the mix. The slabs are made by casting the material in wood or metal moulds. They set quickly. In order to decrease their weight many thicker slabs are cellular. The slabs are bedded and jointed in lime mortar; plaster of Paris may be added.

Plaster boarded Partitions – plasterboard consists of gypsum plaster compressed between two sheets of stout paper. The boards are made in various sizes and are used chiefly for forming ceilings and covering internal partitions.

Wood-Wool Cement Partitions – this material consists of a mixture of wood-wool (wood shavings) and Portland cement: gypsum may be added. Long shavings from 1/8 to 1/4 in.

Wide boards are coated with liquid cement consolidated into slabs by means of a machine press and then stored to mature. These slabs are very light they have good heat and sound insulating qualities, are fire-resistant, can be easily fixed and sawn and provide a good key for the plaster which is applied to the surface after fixing

Asbestos-Cement Partitions – they consist of two flat sheets of asbestos-cement, each approximately 5/12 in. thick, attached to an inner corrugated sheet (1/5 in thick) of similar material. The sheets are jointed in cement mortar and painted or distempered as required. This forms a light, durable, fire-resisting and wall insulated partition.

Metal Partitions – Mild steel and bronze are two of several metals which are used in the manufacture of partitions. These may be designer to consist of a series of panels. The Panels vary from l 1/2 in. Thick.

Steel or 1/8 to 1/4 in. thick bronze. Partitions may also be constructed of bronze or nickel alloys extruded over wood panels or cores.